Governor K K Paul administered the oath of office and secrecy to Justice Pant at a ceremony held at Raj Bhavan here.
Justice Pant had served as a judge of Uttarakhand High Court before being given the new appointment. He is the second Chief Justice to be sworn in within a year of the creation of a separate High Court for Meghalaya after the Parliament gave its nod to the amendment of the North Eastern Areas (Re-Organisation) Act, 1971.
He said, "I am here to serve the people of Meghalaya and I will try to do the best."
Justice T Nandakumar Singh (59) has been the Acting Chief Justice of the Meghalaya High Court.
The High Court of Meghalaya was inaugurated on March 25, this year along with the High Courts of Tripura and Manipur.